feat: integer cents money handling, order page fixes, and vendor filter persistence

Money Handling Architecture:
- Store all monetary values as integer cents (€105.91 = 10591)
- Add app/utils/money.py with Money class and conversion helpers
- Add static/shared/js/money.js for frontend formatting
- Update all database models to use _cents columns (Product, Order, etc.)
- Update CSV processor to convert prices to cents on import
- Add Alembic migration for Float to Integer conversion
- Create .architecture-rules/money.yaml with 7 validation rules
- Add docs/architecture/money-handling.md documentation

Order Details Page Fixes:
- Fix customer name showing 'undefined undefined' - use flat field names
- Fix vendor info empty - add vendor_name/vendor_code to OrderDetailResponse
- Fix shipping address using wrong nested object structure
- Enrich order detail API response with vendor info

Vendor Filter Persistence Fixes:
- Fix orders.js: restoreSavedVendor now sets selectedVendor and filters
- Fix orders.js: init() only loads orders if no saved vendor to restore
- Fix marketplace-letzshop.js: restoreSavedVendor calls selectVendor()
- Fix marketplace-letzshop.js: clearVendorSelection clears TomSelect dropdown
- Align vendor selector placeholder text between pages

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/api/v1/admin/orders.py

@@ -27,7 +27,9 @@ from models.schema.order import (
     AdminOrderStats,
     AdminOrderStatusUpdate,
     AdminVendorsWithOrdersResponse,
+    MarkAsShippedRequest,
     OrderDetailResponse,
+    ShippingLabelInfo,
 )
 
 router = APIRouter(prefix="/orders")
@@ -105,7 +107,14 @@ def get_order_detail(
 ):
     """Get order details including items and addresses."""
     order = order_service.get_order_by_id_admin(db, order_id)
-    return order
+
+    # Enrich with vendor info
+    response = OrderDetailResponse.model_validate(order)
+    if order.vendor:
+        response.vendor_name = order.vendor.name
+        response.vendor_code = order.vendor.vendor_code
+
+    return response
 
 
 @router.patch("/{order_id}/status", response_model=OrderDetailResponse)
@@ -136,3 +145,49 @@ def update_order_status(
 
     db.commit()
     return order
+
+
+@router.post("/{order_id}/ship", response_model=OrderDetailResponse)
+def mark_order_as_shipped(
+    order_id: int,
+    ship_request: MarkAsShippedRequest,
+    db: Session = Depends(get_db),
+    current_admin: User = Depends(get_current_admin_api),
+):
+    """
+    Mark an order as shipped with optional tracking information.
+
+    This endpoint:
+    - Sets order status to 'shipped'
+    - Sets shipped_at timestamp
+    - Optionally stores tracking number, URL, and carrier
+    """
+    order = order_service.mark_as_shipped_admin(
+        db=db,
+        order_id=order_id,
+        tracking_number=ship_request.tracking_number,
+        tracking_url=ship_request.tracking_url,
+        shipping_carrier=ship_request.shipping_carrier,
+    )
+
+    logger.info(
+        f"Admin {current_admin.email} marked order {order.order_number} as shipped"
+    )
+
+    db.commit()
+    return order
+
+
+@router.get("/{order_id}/shipping-label", response_model=ShippingLabelInfo)
+def get_shipping_label_info(
+    order_id: int,
+    db: Session = Depends(get_db),
+    current_admin: User = Depends(get_current_admin_api),
+):
+    """
+    Get shipping label information for an order.
+
+    Returns the shipment number, carrier, and generated label URL
+    based on carrier settings.
+    """
+    return order_service.get_shipping_label_info_admin(db, order_id)